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The sluggish oxygen reduction reaction (ORR) at the cathode largely hinders the practical application of the proton-exchange membrane fuel cells (PEMFCs). Pt-based nanocrystals are the most effective electrocatalysts for the oxygen reduction reaction, however, suffer high cost, scarcity and unsatisfied durability. Herein, we report a new category of annealed multimetallic core-shell catalyst of gold core doped with titanium and platinum-nickel (PtNi) shell with Pt-rich surface as a highly active and robust electrocatalyst for ORR. The introduction of titanium can effectively stabilize the gold core, avoiding the outward migration of Au atoms and ensuring the exposure of Pt-Ni active sites. The experimental findings revealed that the annealed Ti-Au@PtNi NPs catalyst provides 19.26 and 9.84 times higher mass and specific activities than commercial Pt/C catalysts for the oxygen reduction reaction. Moreover, durability tests of annealed Ti-Au@PtNi NPs show no noticeable activity loss even after 20000 potential cycles between 0.6 and 1.0 V vs. RHE, demonstrating a promising catalyst for the oxygen reduction reaction.

Background: Keloid is a disease characterized by proliferation of fibrous tissue after the healing of skin tissue, which seriously affects the daily life of patients. However, the clinical treatment of keloids still has limitations, that is, it is not effective in controlling keloids, resulting in a high recurrence rate. Thus, it is urgent to identify new signatures to improve the diagnosis and treatment of keloids. Method: Bulk RNA seq and scRNA seq data were downloaded from the GEO database. First, we used WGCNA and MEGENA to co-identify keloid/immune-related DEGs. Subsequently, we used three machine learning algorithms (Randomforest, SVM-RFE, and LASSO) to identify hub immune-related genes of keloid (KHIGs) and investigated the heterogeneous expression of KHIGs during fibroblast subpopulation differentiation using scRNA-seq. Finally, we used HE and Masson staining, quantitative reverse transcription-PCR, western blotting, immunohistochemical, and Immunofluorescent assay to investigate the dysregulated expression and the mechanism of retinoic acid in keloids. Results: In the present study, we identified PTGFR, RBP5, and LIF as KHIGs and validated their diagnostic performance. Subsequently, we constructed a novel artificial neural network molecular diagnostic model based on the transcriptome pattern of KHIGs, which is expected to break through the current dilemma faced by molecular diagnosis of keloids in the clinic. Meanwhile, the constructed IG score can also effectively predict keloid risk, which provides a new strategy for keloid prevention. Additionally, we observed that KHIGs were also heterogeneously expressed in the constructed differentiation trajectories of fibroblast subtypes, which may affect the differentiation of fibroblast subtypes and thus lead to dysregulation of the immune microenvironment in keloids. Finally, we found that retinoic acid may treat or alleviate keloids by inhibiting RBP5 to differentiate pro-inflammatory fibroblasts (PIF) to mesenchymal fibroblasts (MF), which further reduces collagen secretion. Conclusion: In summary, the present study provides novel immune signatures (PTGFR, RBP5, and LIF) for keloid diagnosis and treatment, and identifies retinoic acid as potential anti-keloid drugs. More importantly, we provide a new perspective for understanding the interactions between different fibroblast subtypes in keloids and the remodeling of their immune microenvironment.

The purpose of this study was to evaluate the therapeutic effects and mechanism of Qufeng Zhitong (QFZT)capsulefor the treatment of osteoarthritis (OA) in a rat model.

Achieving high activity and durability for the oxygen reduction reaction (ORR) with an ultra-low amount of platinum is significant to promote the widespread application of proton exchange membrane fuel cells (PEMFCs). Here we report a new ultrathin (∼1 nm) ternary PtNiGa alloy nanowires (PtNiGa NWs) electrocatalyst, in which the presence of gallium (Ga) enhances the oxidation resistance of platinum (Pt) and nickel (Ni) and suppresses the dissolution of Ni. The mass and specific activities of PtNiGa NWs are about 11.2 and 7.6 times higher than those of commercial Pt/C catalysts for ORR. Moreover, the mass activity of PtNiGa/C NWs nanocatalyst decreased only by 12.8% and largely retained its electrochemical surface area (ECSA) after 10,000 potential cycles, compared with 38% loss of ECSA for commercial Pt/C catalyst. Therefore, this work provides a general guideline for preparing ternary alloy electrocatalysts and enhancing the activity and stability of the cathode ORR reaction of PEMFCs.

Earth-abundant hematite is an attractive photoanode for photoelectrochemical water splitting, whereas the intrinsic properties of inferior charge transfer and slow water oxidation kinetics still hinder its application. In response, an integrated photoanode has been constructed with hematite nanorod arrays modified by fluorine anion doping and further decorated with amorphous CoAl-layered double hydroxides (CoAl-LDH). This novel CoAl-LDH/F–Fe2O3photoanode exhibited an excellent photocurrent density of 2.46 mA cm–2at 1.23 V versus reversible hydrogen electrode (VRHE), five times enhanced than that of pristine α-Fe2O3. Systematic investigations reveal that fluorine anion serving as a donor dopant dramatically enhances the density of charge carrier and reduces the resistance of hematite for rapid charge transfer. Furthermore, the cocatalyst of CoAl-LDH could effectively passivate the surface defects of F–Fe2O3and facilitate the water oxidation kinetics through an alternative pathway of holes trapped by Co species. As a consequence, the charge separation efficiencies of the bulk and surface were improved to 32.6 and 81.8%, respectively, compared with those of α-Fe2O3(9.7 and 31.7%). Our results demonstrate that the dual modification of the bulk and surface is an attractive maneuver to ameliorate the water oxidation activity of hematite.

The generation of large numbers of functional human hepatocytes for cell-based approaches to liver disease is an important and unmet goal. Direct reprogramming of fibroblasts to hepatic lineages could offer a solution to this problem but so far has only been achieved with mouse cells. Here, we generated human induced hepatocytes (hiHeps) from fibroblasts by lentiviral expression of FOXA3, HNF1A, and HNF4A. hiHeps express hepatic gene programs, can be expanded in vitro, and display functions characteristic of mature hepatocytes, including cytochrome P450 enzyme activity and biliary drug clearance. Upon transplantation into mice with concanavalin-A-induced acute liver failure and fatal metabolic liver disease due to fumarylacetoacetate dehydrolase (Fah) deficiency, hiHeps restore the liver function and prolong survival. Collectively, our results demonstrate successful lineage conversion of nonhepatic human cells into mature hepatocytes with potential for biomedical and pharmaceutical applications.

The hypoxic microenvironment is a clinicopathological characteristic of many diseases, such as rheumatoid arthritis (RA). As a transcription factor activating the gene expression involved in processes such as cell metabolism and angiogenesis, hypoxia-inducible factor (HIF) has a central function in adaption to altered oxygen tension and even contributes to the progression of related diseases. In RA, HIF induces angiogenesis, cell migration, and cartilage destruction, inhibits the apoptosis of synovial cells and inflammatory cells and initiates glycolysis for energy supply by upregulating specific protein levels. HIF expression in RA can be regulated in both oxygen-dependent and independent fashions, leading to the aggravation of this disease. Therefore, HIF is one of the vital RA mediators. Based on the application of HIFtargeted drug research and development in tumors, HIF is a potential therapeutic target for treating RA.

Functional human hepatocytes xenografted into the liver of mice can be used as a model system to study pharmacokinetics, infection of hepatitis viruses, and the efficacy of hepatitis vaccines. Significant levels of liver xeno-repopulation have been reported in Fah−/−Rag2−/−Il2rg−/−mice. However, the high mortality and low breeding rate of this model may hinder its application. A new model, termed Fah−/−Nod/Scidmice, which combines the advantages of liver repopulation in Fah−/−mice with the ease of xenotransplantation in Nod/Scidmice was obtained by gradual cross-breeding. Fah−/−Nod/Scidmice were easily maintained in breeding colonies and in adult animal care facilities. FK506 treatment combined with gradual withdrawal of NTBC before cell transplantation ensured that Fah−/−Nod/Scidmice were susceptible to liver xeno-repopulation by human hepatocytes; the proportion of engrafted human hepatocytes reached 33.6%. The function of the expanded human hepatocytes within the chimeric liver was confirmed by weight curve analysis, the expression of characteristic proteins, and the biochemical analysis of liver function. These results show that Fah−/−Nod/Scidmice are an ideal humanized liver mouse model with many useful applications.

Functional human hepatocytes xeno-engrafted in mouse liver can be used as a model system to study hepatitis virus infection and vaccine efficacy. Significant liver xeno-repopulation has been reported in two kinds of genetically modified mice that have both immune deficiency and liver injury–induced donor hepatocyte selection: the uPA/SCIDmice and Fah−/−Rag2−/−Il2rg−/−mice. The lack of hardy breeding and the overly elaborated technique in these two models may hinder the potential future application of these models to hepatitis virus infection and vaccination studies. Improving the transplantation protocol for liver xeno-repopulation from human hepatocytes will increase the model efficiency and application. In this study, we successfully apply immunosuppressive drug treatments of anti-asialo GM1 and FK506 in Fah−/−Rag2−/−mice, resulting in significant liver xeno-repopulation from human hepatocytes and human fetal liver cells. This methodology decreases the risk of animal mortality during breeding and surgery. When infected with hepatitis B virus (HBV) sera, Fah−/−Rag2−/−mice with liver xeno-repopulation from human hepatocytes accumulate significant levels of HBV DNA and HBV proteins. Our new protocol for humanized liver could be applied in the study of human hepatitis virus infection in vivo, as well as the pharmacokinetics and efficacy of potential vaccines.

This study evaluated the effect of pentazocine pretreatment on fentanyl-induced cough. With ethics committee approval, 277 ASA I-II patients, aged between 19 and 63 years, undergoing various elective surgeries during general anesthesia, were enrolled in this prospective, randomized, double-blind, placebo-controlled clinical trial. All patients were randomly assigned to one of three groups. Group I (n=92) and Group II (n=93) received normal saline, while Group III (n=92) received pentazocine 0.5mg kg–15 min prior to receiving fentanyl, Patients belonging to Groups II and III were administered 2µg/kg fentanyl intravenously over 2s after the first injection; Group I served as a negative control for fentanyl. Physiologic indicators such as heart rate (HR), non-invasive blood pressure (NBP) and pulse oximetry oxygen saturation (SpO2) of patients were recorded before giving pentazocine or normal saline 1 minute after fentanyl injections. The incidence of cough was recorded and graded as mild (1–2), moderate (3–5) and severe (> 5), depending on the number of coughs observed [13]. The incidence of cough was 0%, 22.6% and 4.3% in Group I, Group II and Group III, respectively. There was no significant difference in SpO2for the duration of the trial among the three groups. Premedication with intravenous pentazocine can minimize the incidence of fentanyl-induced cough and has no influence on blood pressure, heart rate, and SpO2compared with Group II.

In this paper, a method of restoring longitudinal images is developed. By using the transfer function for longitudinal objects, and inverse filtering, a longitudinal image may be restored. The Fourier theory and sampling theorems for transverse images cannot be used directly in the longitudinal case. A modification and reasonable approximation are introduced. We have numerically established a necessary relationship between just-resolved longitudinal separation (after inverse filtering), noise level, and the taking conditions of object distance and lens diameter. An empirical formula is also found to well-fit the computed results. This formula may be of use for designing optical systems which are to image longitudinal details, such as in robotics or microscopy.

AbstractWe have systematically investigated the process parameters of laser cladding CPM 10V on AISI 1045 steel substrates. Based on experimental results, we have made reasonable approximations and assumptions, developed a simple but realistic process model, relating the maximum clad thickness and various process parameters, for on-line production. The predicted results of this model are in good agreement with the experimental results. A 2.5 kW continuous-wave: CO 2laser, a coaxial powder feeding system, and a CAD/CAM system were used for laser cladding experiments. The microstructure of cladding layer, interface and heat-affected zone are characterized by using optical microscopy. Microhardness measurements of laser cladding samples under different treatment conditions are also carried out.